Dental operating chair

ABSTRACT

The dental chair has a longitudinally flexible webbing slung between supports at its ends for supporting the patient and also supported intermediate its ends and under the knees of the patient. The foot end support and intermediate support adjust relative to the head end support to conform to patients of different heights and body proportions, and also to adjust for attitude, between an upright sitting position and a substantially horizontal or supine position. The head end support pivots around a point or axis located at the mouth of the patient and the adjustment of other elements provides for pivoting around this axis. The head end pivotal axis is vertically adjustable to accommodate different working positions for the dentist.

United States Patent 91 Page Apr. a, 1973 I54] DENTAL OPERATING CHAIR Primary Examiner-Francis K. Zugel Assistant Examiner-Garry Moore [76] Inventor: Richard W. Page, P. O. Box 2588,

Chatham Mass. 02633 Attorney-Sawyer & Kennedy p 135634 The dental chair has a longitudinally flexible webbing slung between supports at its ends for supporting the [52] US. Cl ..297/284, 297/353 patient and also supported intermediate its ends and [5 1] Int. Cl ..A47c 3/00 under the knees of the patient. The foot and support Field 0! and intermediate support adjust relative to the head 312, 284 end support to conform to patients of different heights and body proportions, and also to adjust for attitude, [56] References C'ted between an upright sitting position and a substantially UNITED STATES PATENTS horizontal or supine position. The head end support pivots around a pomt or axis located at the mouth of 2,000,624 5 1935 Traver ..297/284 the patient and the adjustment f other elements 3,084,978 4/1963 Johansson ..297/397 vides for pivoting around this axis The head end FOREIGN PATENTS OR APPLICATIONS pivotal axis iS vertically adjustable to accommodate different working positions for the dentist. 501,429 '3/l95l Belgium ..297/29 9 Claims, 2 Drawing Figures c\\ IO g I 26 :::::$C/-3 l I Z 123 h 73 7 3 16%.)

A 78, 22 72 I l 3-: Q 27 W8 4 DENTAL OPERATING CHAIR BACKGROUND OF THE INVENTION Earlier dental chairs usually had a vertically adjustable seat, to which the back and leg rest elements were hingedly attached. This permitted placing the patient in an upright sitting position, a supine position or intermediate recumbent positions. Lack of adjustment from hip to knee limited the adaptability of these chairs and they did not permit placing the patient in as low a position as was sometimes required. While arrangements were developed for moving the chair elements so as to pivot around the mouth of the patient, thus permitting a fixed operating location whenever desired, the mechanisms involved tended to be bulky and, perhaps for that reason, such chairs have not come into any widespread use. Later chairs have emphasized curvilinear elements, thus improving appearance and to some degree comfort. However, adjustment has been limited.

SUMMARY OF THE INVENTION The present invention has the object of providing full adjustment of a dental chair with fixed location of the operating area when desired, while avoiding the limitations of prior proposals.

By using a longitudinally flexible webbing elements with suitable terminal and intermediate supports, the invention permits full adaptation to height, proportions and position of the patient. The courses from terminal supports to intermediate support being flexible and under tension will assume catenary forms holding the body in a comfortable S position, the position depending upon the location of of the supports and the size and proportions of the patient. The head end support pivots about an axis passing through the patients mouth while the foot and intermediate supports are adjusted as required. Points of attachment for the webbing may be utilized, as required for particular positionings of the patient. The support for the head end may also be adjusted vertically, as required.

BRIEF DESCRIPTION OF THE DRAWING In the drawing:

FIG. 1 is a somewhat schematic side view of a dental operating chair embodying, the invention in a preferred form;

F IG. 2 is a front view corresponding to FIG. 1.

Referring to the drawing;

There is indicated at 1 the lower or cylinder end of a vertically adjustable support and at 2 the piston or upper end thereof, the member 2 being adjusted vertically in the usual way by hydraulic mechanism, not shown. Arm. 3, carried at the, upper end of member 2, supports the shaft 5 of the chair head end support, the shaft being rotatively joumalled in casing 4, which also contains means (not shown) for angularly adjusting the shaft, for holding it against turning and for releasing it to permit turning. These means may be electric motor, brake and clutch means of any of a variety of available types.

Offset arm 6, secured to androtatablewith shaft 5, forms one side of a back. frame which includes an opposite side frame member 7 andupper and lower frame members 8 and9, respectively. Headrest support 10 is secured to the back frame and carries the vertically (parallel to plane of frame members 6,7) adjustable head rest 11. The specific form of the head rest arrangement forms no part of the present invention, it being sufiicient to note that the usual adjustments permit supporting the patients head so that the mouth is located on the axis of shaft 5. This permits definite location of the operating area.

The flexible webbing or body supporting member is made up, in the embodiment shown by way of illustration, of tension members 12 and surface segments 13, the tension members being link chains and the surface segments being wooden slats 13, the slats being secured to the chains as by riveting, and being spaced, as indicated. At their upper ends 14, the tension elements 12 are secured to frame member 8 and thereby to pivot shaft 5. At their lower ends, the tension members 12 are secured (at 15) to bar 16 forming part of a U- frame, the legs 17 of which are secured to shaft 18 of an adjusting mechanism 19. This mechanism may have a horizontal movement on suitable track or guide rod means (not shown) and serves to place and hold bar 16 in any required position for locating the lower ends 15 of the tension members 12 and properly tensioning the same. Pulley wheels 20 support the tension members 12 at an intermediate point (under the knees of the patient), and are carried by shaft 21 at the ends of arms 22 which are secured to shaft 23 of adjusting mechanism 24, which places and holds shaft 21 and pulley wheels 20 in any desired position. Machanism 24 may have a bodily horizontal adjustment like that of mechanism 19.

The full line position of FIG. 1 shows the chair adjusted for an upright position of a small patient. In this case the back is practically vertical and the head end of flexible support 12-13 (first six slats, as shown) rests against back frame members 6,7 being held in place by releasable clip elements 25. The seat is practically horizontal (three slats wide in FIG. 1) and the balance of flexible member 12-13 from pulleys 20 to bar 16 constitutes leg rest, the lower part of which is not used.

In the dotted line position of FIG. 1, a reclining position is indicated (the parts being indicated by primed reference numerals). The back frame (most of which is now inactive) has been swung up; the flexible support 12-13 runs very slightly downward to the pulleys 20' and. from there to the bar 16'. Head rest 11 (not so shown, to avoid cluttering of lines) will, of course have pivoted along with the back frame generally so that the mouth area remains on the axis of shaft 5.

As will be apparent from the foregoing, a full range of adjustment for size, proportions and position are provided, the operating area (mouth) being kept always in the same place (on axis of angularly adjustable shaft 5). By raising or lowering pedestal support 2, the axis of shaft 5 is correspondingly shifted so as to relocate the mouth in a difierent position, and the same full range of adjustments may be had with referencethereto.

While the embodiment chosen for illustration by way of example uses a webbing member having wood slats and link chain tension members, the invention is not restricted to this specific form of member, but may utilize almost any form of webbing which is longitudinally flexible but substantially still or rigid transversely. The

tension elements may be sprocket chains, or may include the slats or other transverse elements as connecting members between links. The tension elements may also be continuous cable elements or may comprise a molded synthetic resin structure in which transverse stiffening elements are incorporated. Wheels 20 may, in some cases, be replaced by a single roller, and may have teeth engaging in the chain links or between slats. The wheels 20 are normally left free to turn, so as to accommodate shifts of position by the patient, but they may be provided with brake means for locking them in adjusted position, wherever desirable.

The webbing member 12-13 may be covered with fabric, padding or plastic material and may be upholstered or cushioned in a variety of ways to suit such side covering and other mechanisms or furnishings as may be used with the chair.

What is claimed is:

l. A dental operating chair comprising a longitu dinally flexible webbing element, means for holding the ends thereof in predetermined positions for supporting a patient on said webbing and intermediate means for supporting said webbing element adjacent the patients knees, said intermediate means being adjustable to vary its distance from said holding means when in their said predetermined positions and thereby to accommodate patients of different heights.

2. A dental operating chair according to claim 1, in which the said means for holding one end of the webbing element comprises a back frame structure,

means securing the webbing element at the top thereof and a head support carried by and extending beyond said back frame, to locate the patients mouth with respect thereto.

3. A dental operating chair according to claim 2, in which a pivotal support is provided for supporting said back frame with the patient s mouth on its pivotal axis.

4. A dental operating chair according to claim 3, in which said pivotal support is vertically adustable.

5. A dental operating chair according to claim 2, in which the other end support is adjustable, whereby the patients position adjusts between an upright sitting position and a supine one.

6. A dental operating chair according to claim 5, in which the webbing element is transversely stiff.

7. A dental operating chair according to claim 6, in which the webbing element comprises transverse slats and longitudinal tension members secured thereto, the said tension members being secured to the end holding means and resting on the intermediate means.

8. A dental operating chair according to claim 7, in which the intermediate means comprises pulleys and the tension members are chains running over said pulleys.

9. A dental operating chair according to claim 8, in which said back frame has releasable clip holding means for fixing a part of the webbing element to said back. 

1. A dental operating chair comprising a longitudinally flexible webbing element, means for holding the ends thereof in predetermined positions for supporting a patient on said webbing and intermediate means for supporting said webbing element adjacent the patient''s knees, said intermediate means being adjustable to vary its distance from said holding means when in their said predetermined positions and thereby to accommodate patients of different heights.
 2. A dental operating chair according to claim 1, in which the said means for holding one end of the webbing element comprises a back frame structure, means securing the webbing element at the top thereof and a head support carried by and extending beyond said back frame, to locate the patient''s mouth with respect thereto.
 3. A dental operating chair according to claim 2, in which a pivotal support is provided for supporting said back frame with the patient''s mouth on its pivotal axis.
 4. A dental operating chair according to claim 3, in which said pivotal support is vertically adustable.
 5. A dental operating chair according to claim 2, in which the other end support is adjustable, whereby the patient''s position adjusts between an upright sitting position and a supine one.
 6. A dental operating chair according to claim 5, in which the webbing element is transversely stiff.
 7. A dental operating chair according to claim 6, in which the webbing element comprises transverse slats and longitudinal tension members secured thereto, the said tension members being secured to the end holding means and resting on the intermediate means.
 8. A dental operating chair according to claim 7, in which the intermediate means comprises pulleys and the tension members are chains running over said pulleys.
 9. A dental operating chair according to claim 8, in which said back frame has releasable clip holding means for fixing a part of the webbing element to said back. 